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LAB OR A TOR Y G UIDE IN PH YSIOL OGY. 



stant use in muscle-nerve physiology, in circulation, in respiration, 

 and in pharmacology. It must be portable, durable, accurate, read- 

 ily adjustable as to speed and height of drum. All of these quali- 

 ties, together with reasonable cheapness, are possessed by the kym- 

 ograph illustrated in the accompanying figure. This instrument 

 was designed by Mr. C. H. Stoelting, of Chicago, for use in the 

 physiological laboratory of the University of Chicago. It is now 

 used in the University of Michigan, Northwestern University, Mas- 

 sachusetts Institute of Technology and the State Universities of 

 Illinois, Texas and Colorado, in Rush Medical College, and the 

 Detroit Medical College. 



The height of the instrument is 55 cm.; weight 15 ko. The 

 drum is propelled by a clockwork, which is under perfect control 

 of the operator. 



FIG. 1a. 

 FIG. a. Drum supporter with drum and burners. 



2. THE MYOGRAPH. a. The spring myograph, modified from Du 

 Bois Reymond's. b. Simple myograph as used in the physiological 

 laboratory of the Northwestern University, and shown in Fig. 2. 

 c. The crank myograph. 



